var context = document.getElementById('canvas').getContext('2d');

context.fillStyle = 'cornflowerblue';
context.strokeStyle = 'yellow';

context.shadowColor = 'rgba(50, 50, 50, 1.0)';
context.shadowOffsetX = 2;
context.shadowOffsetY = 2;
context.shadowBlur = 4;

context.lineWidth = 20;
context.lineCap = 'round';

context.beginPath();
context.moveTo(120.5, 130);
//绘制贝塞尔曲线，第一个是控制点 第二个是描点
context.quadraticCurveTo(150.8, 130, 160.6, 150.5);
context.quadraticCurveTo(190, 250.0, 210.5, 160.5);
context.quadraticCurveTo(240, 100.5, 290, 70.5);
context.stroke();

